Understanding the difference between composer install and composer update is crucial for managing dependencies in PHP projects.

Example:

1️⃣ Using composer install

- Suppose composer.lock contains Laravel 9.2.1.

- Running composer install will install exactly Laravel 9.2.1, ensuring all team members use the same version.

2️⃣ Using composer update

- If composer.json has "laravel/framework": "^9.0", it means Laravel 9.0+ is allowed.
- Running composer update will fetch the latest compatible version, e.g., Laravel 9.5.0.
- It updates composer.lock with new versions.

When to Use Which?

✅ Use composer install: Reads composer.lock and installs exactly what's listed. when setting up a project or deploying to production.
✅ Use composer update: Updates the dependencies listed in composer.json, and rewrites composer.lock. It’s used when you want to upgrade packages.

Tip: Always commit composer.lock to version control to avoid unexpected version mismatches in production. 🚀

composer install vs composer update – आसान भाषा में अंतर

🛠️ 1. composer install – Jo version mil chuka hai, wahi chahiye

• Ye command composer.lock file ko padhta hai
• Aur usme jo exact version likhe hain, wahi install karta hai
• Ye use tab karo jab:
  • Aapne project clone kiya ho
  • Aap chahte ho sab system pe same dependency version ho

📌 Use karo: Jab project clone karo ya production mein setup karo

🔧 2. composer update – Mujhe naye version chahiye (allowed range ke andar)

• Ye command composer.json file ko padhta hai
• Aur har dependency ka latest matching version download karta hai
• composer.lock file ko bhi update kar deta hai
• Ye use tab karo jab:
  • Aap packages ko latest version pe lana chahte ho
  • Development ke time upgrade karna ho

📌 Use karo: Jab aap packages update karna chahte ho (aur team se sync karlo)

📌 एक लाइन में अंतर:

🔸 composer install = Jo mila tha, wahi chahiye (composer.lock)
🔸 composer update = Naya chahiye, lekin condition ke andar (composer.json)

🎯 Composer Install vs Update – Clone karne ke baad kya karein?

Jab koi developer aapka PHP project GitHub se clone karta hai, to uske paas do important files hoti hain:

• composer.json – Aapne kaunse packages chahiye likha hai
• composer.lock – Aapko kaunse exact version mile woh likha hai

✅ Clone karne ke baad kya command chalani chahiye?

composer install

📌 Ye command kya karega?

• Ye composer.lock file ko padhega
• Aur wahi exact version install karega jo aapke system pe chal raha tha
• Sab developers ke paas same version hoga, koi problem nahi

❌ Agar galti se composer update chala diya?

• Ye composer.json padhega
• Latest allowed versions install karega
• Aur composer.lock file ko update kar dega
• Isse sabke system pe alag-alag version ho sakte hain — problem ho sakti hai

🔑 Simple Rule:

Project clone karo ✅
Fir sirf composer install chalao ✅
composer.lock ko follow karo ✅

✅ Final Note:

Jab bhi project clone karo, hamesha composer install chalana chahiye taaki sabko same version mile aur code stable rahe.